function s1_hello() {
    echo "hello, world!"
}

function s2_tell_who_i_am() {
    whoami
}

function s3_which_distro_do_i_use() {
    if [ -f /etc/os-release ]; then
        source /etc/os-release
        echo "NAME=\"$NAME\""
    else
        echo "无法确定发行版"
    fi
}

function s4_view_my_cpu_arch() {
    uname -m
}

function s5_show_first_scsi_disk_size() {
    local disk_size_bytes=$(lsblk -b | grep -E '^sda' | awk '{print $4}')
    if [ -n "$disk_size_bytes" ]; then
        local disk_size_gb=$(echo "scale=0; $disk_size_bytes / 1000000000" | bc)
        echo "$disk_size_gb"
    else
        echo "未找到第一块 SCSI 硬盘"
    fi
}

function s6_show_main_memory_size_in_megabytes() {
    free -m | grep "Mem:" | awk '{print $2}'
}

